/* =============================================
   RESET & BASE
   ============================================= */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

:root {
  --color-primary:   #1a3a5c;
  --color-accent:    #3a7abf;
  --color-bg:        #eef2f7;
  --color-surface:   #ffffff;
  --color-border:    #ccd6e0;
  --color-text:      #1e2d3d;
  --color-muted:     #5a7590;
  --color-danger:    #c0392b;
  --color-req:       #c0392b;
  --color-valid:     #25833d;
  --color-valid-bg:  #f0faf2;
  --radius:          8px;
  --shadow:          0 2px 10px rgba(26,58,92,0.10);
}

html { font-size: 15px; }

body {
  font-family: "Segoe UI", system-ui, -apple-system, sans-serif;
  background-color: var(--color-bg);
  background-image: url("assets/background.jpg");
  background-size: cover;
  background-attachment: fixed;
  background-position: center;
  color: var(--color-text);
  line-height: 1.55;
  min-height: 100vh;
}

/* =============================================
   HEADER
   ============================================= */
.site-header {
  background-color: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(6px);
  border-bottom: 3px solid var(--color-accent);
  padding: 18px 32px;
  display: flex;
  align-items: center;
  gap: 20px;
  box-shadow: 0 2px 12px rgba(26,58,92,0.15);
}

.site-logo {
  height: 60px;
  width: auto;
  object-fit: contain;
  flex-shrink: 0;
}

.header-text {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.site-title {
  font-size: 1.45rem;
  font-weight: 700;
  color: var(--color-primary);
  letter-spacing: 0.01em;
}

.site-subtitle {
  font-size: 0.82rem;
  color: var(--color-muted);
  font-weight: 500;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

/* =============================================
   PAGE WRAPPER
   ============================================= */
.page-wrapper {
  max-width: 1100px;
  margin: 32px auto 48px;
  padding: 0 20px;
}

/* =============================================
   FORM SECTIONS
   ============================================= */
.form-section {
  background-color: rgba(255, 255, 255, 0.97);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 24px 28px;
  margin-bottom: 20px;
  box-shadow: var(--shadow);
}

.section-title {
  font-size: 0.78rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.09em;
  color: var(--color-primary);
  border-bottom: 2px solid var(--color-accent);
  padding-bottom: 8px;
  margin-bottom: 20px;
}

/* =============================================
   FIELD BOX
   ============================================= */
.field-box {
  display: flex;
  flex-direction: column;
  gap: 5px;
  margin-bottom: 14px;
}

.field-box label {
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--color-muted);
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.field-box input {
  border: 1px solid var(--color-border);
  border-radius: 5px;
  padding: 8px 10px;
  font-size: 0.93rem;
  color: var(--color-text);
  background: #fafdff;
  transition: border-color 0.18s, box-shadow 0.18s, background-color 0.18s;
  width: 100%;
}

.field-box input:focus {
  outline: none;
  border-color: var(--color-accent);
  box-shadow: 0 0 0 3px rgba(58,122,191,0.15);
  background: #ffffff;
}

.field-box input:invalid:not(:placeholder-shown) {
  border-color: var(--color-danger);
}

.field-box input:required:valid,
.field-box input[pattern]:valid:not(:placeholder-shown) {
  border-color: var(--color-valid);
  background-color: var(--color-valid-bg);
  box-shadow: 0 0 0 2px rgba(37, 131, 61, 0.12);
}

/* =============================================
   REQUIRED MARK
   ============================================= */
.req-mark {
  color: var(--color-req);
  font-weight: 700;
  margin-left: 2px;
}

/* =============================================
   TWO COLUMN LAYOUT
   ============================================= */
.two-column {
  display: flex;
  gap: 16px;
}

.two-column .field-box {
  flex: 1;
}

/* =============================================
   CONTAINER GRID (6 columns)
   ============================================= */
.container-grid {
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  gap: 12px;
}

/* =============================================
   DATE GRID (3 columns)
   ============================================= */
.date-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 14px;
}

.date-grid .field-box {
  margin-bottom: 0;
}

/* =============================================
   COMPACT FIELDS
   ============================================= */
.compact-field input {
  padding: 7px 8px;
  font-size: 0.87rem;
}

.calculated-output {
  display: flex;
  align-items: center;
  min-height: 36px;
  width: 100%;
  padding: 7px 8px;
  border: 1px solid var(--color-valid);
  border-radius: 5px;
  background-color: var(--color-valid-bg);
  color: var(--color-text);
  font-size: 0.87rem;
  font-weight: 700;
}

/* =============================================
   ACTION BAR
   ============================================= */
.action-bar {
  display: flex;
  justify-content: flex-end;
  align-items: center;
  gap: 12px;
  padding: 18px 0 8px;
}

.req-note {
  font-size: 0.8rem;
  color: var(--color-muted);
  margin-right: auto;
}

.btn {
  padding: 11px 34px;
  font-size: 0.95rem;
  font-weight: 600;
  border: none;
  border-radius: 6px;
  cursor: pointer;
  transition: background 0.18s, transform 0.1s, box-shadow 0.18s;
  letter-spacing: 0.03em;
}

.btn:active {
  transform: translateY(1px);
}

.btn-reset {
  background-color: #ffffff;
  color: var(--color-muted);
  border: 1px solid var(--color-border);
}

.btn-reset:hover {
  background-color: #e8eef5;
  color: var(--color-text);
}

.btn-submit {
  background-color: var(--color-accent);
  color: #ffffff;
  box-shadow: 0 2px 8px rgba(58,122,191,0.30);
}

.btn-submit:hover {
  background-color: #2c66a8;
  box-shadow: 0 4px 14px rgba(58,122,191,0.40);
}

/* =============================================
   FOOTER
   ============================================= */
.site-footer {
  text-align: center;
  padding: 16px;
  font-size: 0.78rem;
  color: #ffffff;
  background: rgba(26, 58, 92, 0.75);
  backdrop-filter: blur(4px);
  letter-spacing: 0.03em;
}

/* =============================================
   RESPONSIVE — 700px and below
   ============================================= */
@media (max-width: 700px) {
  .site-header {
    padding: 14px 16px;
    gap: 12px;
  }

  .site-logo {
    height: 44px;
  }

  .site-title {
    font-size: 1.1rem;
  }

  .page-wrapper {
    margin-top: 18px;
    padding: 0 10px;
  }

  .form-section {
    padding: 16px 14px;
  }

  .two-column {
    flex-direction: column;
    gap: 0;
  }

  .container-grid {
    grid-template-columns: repeat(3, 1fr);
  }

  .date-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .action-bar {
    flex-wrap: wrap;
  }

  .req-note {
    width: 100%;
    margin-right: 0;
  }

  .btn {
    flex: 1;
    text-align: center;
  }
}

@media (max-width: 420px) {
  .container-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .date-grid {
    grid-template-columns: 1fr;
  }
}